1
|
Batalov AI, Zakharova NE, Pronin IN, Belyaev AY, Pogosbekyan EL, Goryaynov SA, Bykanov AE, Tyurina AN, Shevchenko AM, Solozhentseva KD, Nikitin PV, Potapov AA. 3D pCASL-perfusion in preoperative assessment of brain gliomas in large cohort of patients. Sci Rep 2022; 12:2121. [PMID: 35136119 PMCID: PMC8826414 DOI: 10.1038/s41598-022-05992-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 01/18/2022] [Indexed: 01/02/2023] Open
Abstract
The aim of the study was to evaluate the role of pseudocontinuous arterial spin labeling perfusion (pCASL-perfusion) in preoperative assessment of cerebral glioma grades. The study group consisted of 253 patients, aged 7-78 years with supratentorial gliomas (65 low-grade gliomas (LGG), 188 high-grade gliomas (HGG)). We used 3D pCASL-perfusion for each patient in order to calculate the tumor blood flow (TBF). We obtained maximal tumor blood flow (maxTBF) in small regions of interest (30 ± 10 mm2) and then normalized absolute maximum tumor blood flow (nTBF) to that of the contralateral normal-appearing white matter of the centrum semiovale. MaxTBF and nTBF values significantly differed between HGG and LGG groups (p < 0.001), as well as between patient groups separated by the grades (grade II vs. grade III) (p < 0.001). Moreover, we performed ROC-analysis which demonstrated high sensitivity and specificity in differentiating between HGG and LGG. We found significant differences for maxTBF and nTBF between grade III and IV gliomas, however, ROC-analysis showed low sensitivity and specificity. We did not observe a significant difference in TBF for astrocytomas and oligodendrogliomas. Our study demonstrates that 3D pCASL-perfusion as an effective diagnostic tool for preoperative differentiation of glioma grades.
Collapse
Affiliation(s)
- A I Batalov
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - N E Zakharova
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - I N Pronin
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - A Yu Belyaev
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - E L Pogosbekyan
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - S A Goryaynov
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - A E Bykanov
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - A N Tyurina
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - A M Shevchenko
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation.
| | - K D Solozhentseva
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - P V Nikitin
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - A A Potapov
- Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation, Moscow, Russian Federation
| |
Collapse
|
2
|
Robson PM, Vergani V, Benkert T, Trivieri MG, Karakatsanis NA, Abgral R, Dweck MR, Moreno PR, Kovacic JC, Block KT, Fayad ZA. Assessing the qualitative and quantitative impacts of simple two-class vs multiple tissue-class MR-based attenuation correction for cardiac PET/MR. J Nucl Cardiol 2021; 28:2194-2204. [PMID: 31898004 PMCID: PMC7329599 DOI: 10.1007/s12350-019-02002-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 11/01/2019] [Indexed: 10/25/2022]
Abstract
BACKGROUND Hybrid PET/MR imaging has significant potential in cardiology due to its combination of molecular PET imaging and cardiac MR. Multi-tissue-class MR-based attenuation correction (MRAC) is necessary for accurate PET quantification. Moreover, for thoracic PET imaging, respiration is known to lead to misalignments of MRAC and PET data that result in PET artifacts. These factors can be addressed by using multi-echo MR for tissue segmentation and motion-robust or motion-gated acquisitions. However, the combination of these strategies is not routinely available and can be prone to errors. In this study, we examine the qualitative and quantitative impacts of multi-class MRAC compared to a more widely available simple two-class MRAC for cardiac PET/MR. METHODS AND RESULTS In a cohort of patients with cardiac sarcoidosis, we acquired MRAC data using multi-echo radial gradient-echo MR imaging. Water-fat separation was used to produce attenuation maps with up to 4 tissue classes including water-based soft tissue, fat, lung, and background air. Simultaneously acquired 18F-fluorodeoxyglucose PET data were subsequently reconstructed using each attenuation map separately. PET uptake values were measured in the myocardium and compared between different PET images. The inclusion of lung and subcutaneous fat in the MRAC maps significantly affected the quantification of 18F-fluorodeoxyglucose activity in the myocardium but only moderately altered the appearance of the PET image without introduction of image artifacts. CONCLUSION Optimal MRAC for cardiac PET/MR applications should include segmentation of all tissues in combination with compensation for the respiratory-related motion of the heart. Simple two-class MRAC is adequate for qualitative clinical assessment.
Collapse
Affiliation(s)
- Philip M Robson
- Translational and Molecular Imaging Institute, Leon and Norma Hess Center for Science and Medicine, Icahn School of Medicine at Mount Sinai, One Gustave Levy Pl, 1470 Madison Ave, TMII - 1st floor, New York, NY, 10029, USA.
| | - Vittoria Vergani
- Translational and Molecular Imaging Institute, Leon and Norma Hess Center for Science and Medicine, Icahn School of Medicine at Mount Sinai, One Gustave Levy Pl, 1470 Madison Ave, TMII - 1st floor, New York, NY, 10029, USA
- Cardiothoracic and Vascular Department, Vita-Salute University and San Raffaele Hospital, Milan, Italy
| | - Thomas Benkert
- Center for Advanced Imaging Innovation and Research, Department of Radiology, New York University School of Medicine, New York, NY, USA
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - Maria Giovanna Trivieri
- Translational and Molecular Imaging Institute, Leon and Norma Hess Center for Science and Medicine, Icahn School of Medicine at Mount Sinai, One Gustave Levy Pl, 1470 Madison Ave, TMII - 1st floor, New York, NY, 10029, USA
- Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, One Gustave Levy Pl, New York, NY, 10029, USA
| | - Nicolas A Karakatsanis
- Translational and Molecular Imaging Institute, Leon and Norma Hess Center for Science and Medicine, Icahn School of Medicine at Mount Sinai, One Gustave Levy Pl, 1470 Madison Ave, TMII - 1st floor, New York, NY, 10029, USA
- Division of Radiopharmaceutical Sciences, Department of Radiology, Weill Cornell Medical College, Cornell University, New York, NY, USA
| | - Ronan Abgral
- Department of Nuclear Medicine, University Hospital of Brest, European University of Brittany, EA3878 GETBO, Brest, France
| | - Marc R Dweck
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Pedro R Moreno
- Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, One Gustave Levy Pl, New York, NY, 10029, USA
| | - Jason C Kovacic
- Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, One Gustave Levy Pl, New York, NY, 10029, USA
| | - Kai Tobias Block
- Center for Advanced Imaging Innovation and Research, Department of Radiology, New York University School of Medicine, New York, NY, USA
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - Zahi A Fayad
- Translational and Molecular Imaging Institute, Leon and Norma Hess Center for Science and Medicine, Icahn School of Medicine at Mount Sinai, One Gustave Levy Pl, 1470 Madison Ave, TMII - 1st floor, New York, NY, 10029, USA
| |
Collapse
|
3
|
Andrews JPM, MacNaught G, Moss AJ, Doris MK, Pawade T, Adamson PD, van Beek EJR, Lucatelli C, Lassen ML, Robson PM, Fayad ZA, Kwiecinski J, Slomka PJ, Berman DS, Newby DE, Dweck MR. Cardiovascular 18F-fluoride positron emission tomography-magnetic resonance imaging: A comparison study. J Nucl Cardiol 2021; 28:1-12. [PMID: 31792913 PMCID: PMC8616877 DOI: 10.1007/s12350-019-01962-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 11/01/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND 18F-Fluoride uptake denotes calcification activity in aortic stenosis and atherosclerosis. While PET/MR has several advantages over PET/CT, attenuation correction of PET/MR data is challenging, limiting cardiovascular application. We compared PET/MR and PET/CT assessments of 18F-fluoride uptake in the aortic valve and coronary arteries. METHODS AND RESULTS 18 patients with aortic stenosis or recent myocardial infarction underwent 18F-fluoride PET/CT followed immediately by PET/MR. Valve and coronary 18F-fluoride uptake were evaluated independently. Both standard (Dixon) and novel radial GRE) MR attenuation correction (AC) maps were validated against PET/CT with results expressed as tissue-to-background ratios (TBRs). Visually, aortic valve 18F-fluoride uptake was similar on PET/CT and PET/MR. TBRMAX values were comparable with radial GRE AC (PET/CT 1.55±0.33 vs. PET/MR 1.58 ± 0.34, P = 0.66; 95% limits of agreement - 27% to + 25%) but performed less well with Dixon AC (1.38 ± 0.44, P = 0.06; bias (-)14%; 95% limits of agreement - 25% to + 53%). In native coronaries, 18F-fluoride uptake was similar on PET/MR to PET/CT regardless of AC approach. PET/MR identified 28/29 plaques identified on PET/CT; however, stents caused artifact on PET/MR making assessment of 18F-fluoride uptake challenging. CONCLUSION Cardiovascular PET/MR demonstrates good visual and quantitative agreement with PET/CT. However, PET/MR is hampered by stent-related artifacts currently limiting clinical application.
Collapse
Affiliation(s)
- Jack P M Andrews
- British Heart Foundation Centre of Cardiovascular Sciences, University of Edinburgh, Room SU.305, Chancellor's building, 51 Little France Crescent, University of Edinburgh, Edinburgh, EH16 4SB, UK.
| | - Gillian MacNaught
- Edinburgh Imaging, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Alastair J Moss
- British Heart Foundation Centre of Cardiovascular Sciences, University of Edinburgh, Room SU.305, Chancellor's building, 51 Little France Crescent, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | - Mhairi K Doris
- British Heart Foundation Centre of Cardiovascular Sciences, University of Edinburgh, Room SU.305, Chancellor's building, 51 Little France Crescent, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | - Tania Pawade
- British Heart Foundation Centre of Cardiovascular Sciences, University of Edinburgh, Room SU.305, Chancellor's building, 51 Little France Crescent, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | - Philip D Adamson
- British Heart Foundation Centre of Cardiovascular Sciences, University of Edinburgh, Room SU.305, Chancellor's building, 51 Little France Crescent, University of Edinburgh, Edinburgh, EH16 4SB, UK
- Christchurch Heart Institute, University of Otago, Christchurch, New Zealand
| | - Edwin J R van Beek
- Edinburgh Imaging, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Christophe Lucatelli
- Edinburgh Imaging, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | | | | | - Zahi A Fayad
- Icahn School of Medicine at Mount Sinai, New York, PA, USA
| | - Jacek Kwiecinski
- British Heart Foundation Centre of Cardiovascular Sciences, University of Edinburgh, Room SU.305, Chancellor's building, 51 Little France Crescent, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | | | | | - David E Newby
- British Heart Foundation Centre of Cardiovascular Sciences, University of Edinburgh, Room SU.305, Chancellor's building, 51 Little France Crescent, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | - Marc R Dweck
- British Heart Foundation Centre of Cardiovascular Sciences, University of Edinburgh, Room SU.305, Chancellor's building, 51 Little France Crescent, University of Edinburgh, Edinburgh, EH16 4SB, UK
| |
Collapse
|
4
|
Abstract
Cardiac magnetic resonance imaging (CMR) is an important tool for the non-invasive diagnosis of a variety of cardiovascular diseases. Parametric mapping with multi-contrast CMR is able to quantify tissue alterations in myocardial disease and promises to improve patient care. However, magnetic resonance imaging is an inherently slow imaging modality, resulting in long acquisition times for parametric mapping which acquires a series of cardiac images with different contrasts for signal fitting or dictionary matching. Furthermore, extra efforts to deal with respiratory and cardiac motion by triggering and gating further increase the scan time. Several techniques have been developed to speed up CMR acquisitions, which usually acquire less data than that required by the Nyquist-Shannon sampling theorem, followed by regularized reconstruction to mitigate undersampling artefacts. Recent advances in CMR parametric mapping speed up CMR by synergistically exploiting spatial-temporal and contrast redundancies. In this article, we will review the recent developments in multi-contrast CMR image reconstruction for parametric mapping with special focus on low-rank and model-based reconstructions. Deep learning-based multi-contrast reconstruction has recently been proposed in other magnetic resonance applications. These developments will be covered to introduce the general methodology. Current technical limitations and potential future directions are discussed. This article is part of the theme issue 'Synergistic tomographic image reconstruction: part 1'.
Collapse
Affiliation(s)
- Haikun Qi
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, London SE1 7EH, UK
| | - Gastao Cruz
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, London SE1 7EH, UK
| | - René Botnar
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, London SE1 7EH, UK
- Escuela de Ingeniería, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Claudia Prieto
- School of Biomedical Engineering and Imaging Sciences, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, London SE1 7EH, UK
- Escuela de Ingeniería, Pontificia Universidad Católica de Chile, Santiago, Chile
| |
Collapse
|
5
|
Wang X, Tan Z, Scholand N, Roeloffs V, Uecker M. Physics-based reconstruction methods for magnetic resonance imaging. Philos Trans A Math Phys Eng Sci 2021; 379:20200196. [PMID: 33966457 PMCID: PMC8107652 DOI: 10.1098/rsta.2020.0196] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/01/2021] [Indexed: 05/03/2023]
Abstract
Conventional magnetic resonance imaging (MRI) is hampered by long scan times and only qualitative image contrasts that prohibit a direct comparison between different systems. To address these limitations, model-based reconstructions explicitly model the physical laws that govern the MRI signal generation. By formulating image reconstruction as an inverse problem, quantitative maps of the underlying physical parameters can then be extracted directly from efficiently acquired k-space signals without intermediate image reconstruction-addressing both shortcomings of conventional MRI at the same time. This review will discuss basic concepts of model-based reconstructions and report on our experience in developing several model-based methods over the last decade using selected examples that are provided complete with data and code. This article is part of the theme issue 'Synergistic tomographic image reconstruction: part 1'.
Collapse
Affiliation(s)
- Xiaoqing Wang
- Institute for Diagnostic and Interventional Radiology, University Medical Center Göttingen, Göttingen, Germany
- Partner Site Göttingen, German Centre for Cardiovascular Research (DZHK), Göttingen, Germany
| | - Zhengguo Tan
- Institute for Diagnostic and Interventional Radiology, University Medical Center Göttingen, Göttingen, Germany
- Partner Site Göttingen, German Centre for Cardiovascular Research (DZHK), Göttingen, Germany
| | - Nick Scholand
- Institute for Diagnostic and Interventional Radiology, University Medical Center Göttingen, Göttingen, Germany
- Partner Site Göttingen, German Centre for Cardiovascular Research (DZHK), Göttingen, Germany
| | - Volkert Roeloffs
- Institute for Diagnostic and Interventional Radiology, University Medical Center Göttingen, Göttingen, Germany
| | - Martin Uecker
- Institute for Diagnostic and Interventional Radiology, University Medical Center Göttingen, Göttingen, Germany
- Partner Site Göttingen, German Centre for Cardiovascular Research (DZHK), Göttingen, Germany
- Cluster of Excellence ‘Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells’ (MBExC), University of Göttingen, Göttingen, Germany
- Campus Institute Data Science (CIDAS), University of Göttingen, Göttingen, Germany
| |
Collapse
|
6
|
ATASOY D, CANSU A, BEKİRÇAVUŞOĞLU AF, BAHAT ÖZDOĞAN E, AHMETOĞLU A. The utility of magnetic resonance angiography in children with nutcracker syndrome. Turk J Med Sci 2021; 51:2396-2402. [PMID: 33992039 PMCID: PMC8742473 DOI: 10.3906/sag-2101-14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Accepted: 05/15/2021] [Indexed: 11/03/2022] Open
Abstract
Backgroun/Aim: The presented study aimed to evaluate the utility of Magnetic Resonance Angiography in the pediatric population with nutcracker syndrome. MATERIALS AND METHODS Patients with suggestive clinical symptoms and laboratory findings and got the diagnosis of nutcracker syndrome with Doppler ultrasonography between January 2011-2019 were included in the study. In addition, children who had renal MRA due to hypertension were evaluated as the control group. MRA images of all patients were examined retrospectively by 3 radiologists at different levels of experience, and the superior mesenteric artery angle, aorta-mesenteric distance, left renal vein diameter both in the regions of aorta-mesenteric and renal hilum were recorded. RESULTS Forty-five patients diagnosed with nutcracker syndrome were included in the study. The mean age of patients was 12 (4-16) and 30 (67%) were female. As the control group, 25 patients with hypertension who had MRA were included and they had a mean age of 12 (1-18) and 19 (76%) were male. The mean superior mesenteric artery angle was 26.5 ° (16-73 ± 12) in the patient group and 57.8 ° (25-139, ± 33) in the control group (p <0.001); the mean aorta-mesenteric distance was 3.3 mm (1.7-6.5, ± 1.1) in the patient group and 8 mm (3.4-32, ± 5.9) in the control group (p <0.001). MRA measurements of 3 radiologists were consistent with each other. CONCLUSIONS MRA imaging can be applied as an alternative diagnostic method for Doppler ultrasonography and Multidetector CT examinations by radiologists with different experience levels in pediatric patients with nutcracker syndrome.
Collapse
Affiliation(s)
- Dilara ATASOY
- Department of Radiology, Sivas Numune Hospital, SivasTurkey
- * To whom correspondence should be addressed. E-mail:
| | - Ayşegül CANSU
- Department of Radiology, Faculty of Medicine, Karadeniz Technical University, TrabzonTurkey
| | | | - Elif BAHAT ÖZDOĞAN
- Division of Pediatric Nephrology, Department of Pediatrics, Faculty of Medicine, Karadeniz Technical University, TrabzonTurkey
| | - Ali AHMETOĞLU
- Department of Radiology, Faculty of Medicine, Karadeniz Technical University, TrabzonTurkey
| |
Collapse
|
7
|
Tavares de Sousa M, Hecher K, Yamamura J, Kording F, Ruprecht C, Fehrs K, Behzadi C, Adam G, Schoennagel BP. Dynamic fetal cardiac magnetic resonance imaging in four-chamber view using Doppler ultrasound gating in normal fetal heart and in congenital heart disease: comparison with fetal echocardiography. Ultrasound Obstet Gynecol 2019; 53:669-675. [PMID: 30381848 DOI: 10.1002/uog.20167] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 09/20/2018] [Accepted: 09/20/2018] [Indexed: 06/08/2023]
Abstract
OBJECTIVES To investigate the diagnostic performance of dynamic fetal cardiac magnetic resonance imaging (MRI), using a MR-compatible Doppler ultrasound (DUS) device for fetal cardiac gating, in differentiating fetuses with congenital heart disease from those with a normal heart, and to compare the technique with fetal echocardiography. METHODS This was a prospective study of eight fetuses with a normal heart and four with congenital heart disease (CHD), at a median of 34 (range, 28-36) weeks' gestation. Dynamic fetal cardiac MRI was performed using a DUS device for direct cardiac gating. The four-chamber view was evaluated according to qualitative findings. Measurements of the length of the left and right ventricles, diameter of the tricuspid and mitral valves, myocardial wall thickness, transverse cardiac diameter and left ventricular planimetry were performed. Fetal echocardiography and postnatal diagnoses were considered the reference standards. RESULTS Direct cardiac gating allowed continuous triggering of the fetal heart, showing high temporal and spatial resolution. Both fetal cardiac MRI and echocardiography in the four-chamber view detected pathological findings in three of the 12 fetuses. Qualitative evaluation revealed overall consistency between echocardiography and MRI. On both echocardiography and MRI, quantitative measurements revealed significant differences between fetuses with a normal heart and those with CHD with respect to the length of the right (P < 0.01 for both) and left (P < 0.01 for both) ventricles and transverse cardiac diameter (P < 0.05 and P < 0.01, respectively). Tricuspid valve diameter on cardiac MRI was found to be significantly different in healthy fetuses from in those with CHD (P < 0.05). CONCLUSIONS For the first time, this study has shown that dynamic fetal cardiac MRI in the four-chamber view, using external cardiac gating, allows evaluation of cardiac anatomy and diagnosis of congenital heart disease in agreement with fetal echocardiography. Dynamic fetal cardiac MRI may be useful as a second-line investigation if conditions for fetal echocardiography are unfavorable. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Collapse
Affiliation(s)
- M Tavares de Sousa
- University Medical Center Hamburg-Eppendorf, Department of Obstetrics and Fetal Medicine, Hamburg, Germany
| | - K Hecher
- University Medical Center Hamburg-Eppendorf, Department of Obstetrics and Fetal Medicine, Hamburg, Germany
| | - J Yamamura
- University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Radiology and Nuclear Medicine, Hamburg, Germany
| | - F Kording
- University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Radiology and Nuclear Medicine, Hamburg, Germany
| | - C Ruprecht
- University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Radiology and Nuclear Medicine, Hamburg, Germany
| | - K Fehrs
- University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Radiology and Nuclear Medicine, Hamburg, Germany
| | - C Behzadi
- University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Radiology and Nuclear Medicine, Hamburg, Germany
| | - G Adam
- University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Radiology and Nuclear Medicine, Hamburg, Germany
| | - B P Schoennagel
- University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Radiology and Nuclear Medicine, Hamburg, Germany
| |
Collapse
|
8
|
Saini J, Gupta RK, Kumar M, Singh A, Saha I, Santosh V, Beniwal M, Kandavel T, Cauteren MV. Comparative evaluation of cerebral gliomas using rCBV measurements during sequential acquisition of T1-perfusion and T2*-perfusion MRI. PLoS One 2019; 14:e0215400. [PMID: 31017934 PMCID: PMC6481809 DOI: 10.1371/journal.pone.0215400] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 04/01/2019] [Indexed: 12/31/2022] Open
Abstract
Objective To assess the inter-technique agreement of relative cerebral blood volume (rCBV) measurements obtained using T1- and T2*-perfusion MRI on 3T scanner in glioma patients. Methods A total of 49 adult patients with gliomas underwent both on T1- and T2*-perfusion in the same scanning session, and rCBV maps were estimated using both methods. For the quantitative analysis; Two independent observers recorded the rCBV values from the tumor as well as contralateral brain tissue from both T1- and T2*-perfusion. Inter-observer and inter-technique rCBV measurement agreement were determined by using 95% Bland-Altman limits of agreement and intra-class correlation coefficient (ICC) statistics. Results Qualitative analysis of the conventional and perfusion images showed that 16/49 (32.65%) tumors showed high susceptibility, and in these patients T2*-perfusion maps were suboptimal. Bland-Altman plots revealed an agreement between two independent observers recorded rCBV values for both T1- and T2*-perfusion. The ICC demonstrated strong agreement between rCBV values recorded by two observers for both T2* (ICC = 0.96, p = 0.040) and T1 (ICC = 0.97, p = 0.026) perfusion and similarly, good agreement was noted between rCBV estimated using two methods (ICC = 0.74, P<0.001). ROC analysis showed that rCBV estimated using T1- and T2*-perfusion methods were able to discriminate between grade-III and grade-IV tumors with AUC of 0.723 and 0.767 respectively. Comparison of AUC values of two ROC curves did not show any significant difference. Conclusions In the current study, T1- and T2*-perfusion showed similar diagnostic performance for discrimination of grade III and grade IV gliomas; however, T1-perfusion was found to be better for the evaluation of tumors with intratumoral hemorrhage, postoperative recurrent tumors, and lesions near skull base. We conclude that T1-perfusion MRI with a single dose of contrast could be used as an alternative to T2*-perfusion to overcome the issues associated with this technique in brain tumors for reliable perfusion quantification.
Collapse
Affiliation(s)
- Jitender Saini
- Department of Neuroimaging & Interventional Radiology, National Institute of Mental, Health and Neurosciences, Bangalore, Karnataka, India
- * E-mail:
| | - Rakesh Kumar Gupta
- Department of Radiology and Imaging, Fortis Memorial Hospital and Research Institute, Gurgaon, Haryana, India
| | - Manoj Kumar
- Department of Neuroimaging & Interventional Radiology, National Institute of Mental, Health and Neurosciences, Bangalore, Karnataka, India
| | - Anup Singh
- Center for Biomedical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
| | - Indrajit Saha
- Philips Health Systems, Philips India Limited, Gurgaon, Haryana, India
| | - Vani Santosh
- Department of Neuropathology, National Institute of Mental, Health and Neurosciences, Bangalore, Karnataka, India
| | - Manish Beniwal
- Department of Neurosurgery, National Institute of Mental, Health and Neurosciences, Bangalore, Karnataka, India
| | - Thennarasu Kandavel
- Department of Biostatistics, National Institute of Mental, Health and Neurosciences, Bangalore, Karnataka, India
| | | |
Collapse
|
9
|
Mahawish KM, Bowers A, DeCaigney S. Local experience with methamphetamine associated stroke at a small district health board. N Z Med J 2019; 132:105-108. [PMID: 30703785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Affiliation(s)
- Karim M Mahawish
- Consultant Physician, Department of Medicine, Rotorua Hospital, Bay of Plenty
| | - Andrew Bowers
- Consultant Physician, Department of Medicine, Rotorua Hospital, Bay of Plenty
| | - Susan DeCaigney
- Consultant Physician, Department of Medicine, Rotorua Hospital, Bay of Plenty
| |
Collapse
|
10
|
Guler TE, Yalin K, Aksu T, Golcuk E, Sanli S, Kaya Bilge A, Adalet K. Prognostic value role of radiofrequency lesion size by cardiac magnetic resonance imaging on outcomes of ablation in patients with ischemic scar-related ventricular tachycardia: A single center pilot study. Medicine (Baltimore) 2018; 97:e12955. [PMID: 30431569 PMCID: PMC6257390 DOI: 10.1097/md.0000000000012955] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Inadequate ablation lesion formation may be responsible for post-ablation ventricular tachycardia (VT) recurrences.We aimed to evaluate whether visualisation of radiofrequency (RF) lesion size by cardiac magnetic resonance imaging (CMR) has any role in predicting adequacy of lesion and in estimating outcome.Retrospective pilot studyNine consecutive patients (8 male, age 60 ± 13 years) underwent ablation for sustained VT because of ischemic scar were evaluated for pre- and post-procedure scar tissue by CMR to characterize ablation lesions. Microvascular obstruction (MVO) surrounded by late gadolinium enhancement was defined as irreversible RF lesion. All patients were followed for at least 6 months for recurrences.Five of the patients had previous inferior myocardial infarction (MI), whereas remaining 4 had anterior MI. Acute procedural success, as defined by termination of the arrhythmia without recurrence in 30 minutes, was attained in all patients. Contrast enhancement and wall motion abnormality in presumed infarction area were confirmed by pre-ablation CMR images. MVO was detected at the reported ablation site in 6/9 patients, all arrhythmia- and symptom-free at median 24 months (range 8-38 months) follow-up. In remaining 3 patients who had VT recurrence (clinical VT in 2, sustain VT with a new morphology in 1), MVO was not detected despite achievement of acute procedural success. There was no correlation with pre-ablation scar size and clinical arrhythmia recurrence.CMR is a useful imaging modality to guide ablation procedures by detecting scar tissue. Additionally MVO seen by post-procedural imaging may be related to adequacy of RF ablation lesions and may correlate with clinical outcome.
Collapse
Affiliation(s)
- Tümer Erdem Guler
- University of Health Sciences, Kocaeli Derince Education and Research Hospital, Department of Cardiology, Kocaeli
| | - Kivanç Yalin
- Usak University, Faculty of Medicine, Department of Cardiology, Usak
| | - Tolga Aksu
- University of Health Sciences, Kocaeli Derince Education and Research Hospital, Department of Cardiology, Kocaeli
| | - Ebru Golcuk
- Balikesir University, Faculty of Medicine, Department of Cardiology, Balikesir
| | | | - Ahmet Kaya Bilge
- Istanbul University, Istanbul Faculty of Medicine, Department of Cardiology, Istanbul, Turkey
| | - Kamil Adalet
- Istanbul University, Istanbul Faculty of Medicine, Department of Cardiology, Istanbul, Turkey
| |
Collapse
|
11
|
Ma M, Diao KY, Yang ZG, Zhu Y, Guo YK, Yang MX, Zhang Y, He Y. Clinical associations of microvascular obstruction and intramyocardial hemorrhage on cardiovascular magnetic resonance in patients with acute ST segment elevation myocardial infarction (STEMI): An observational cohort study. Medicine (Baltimore) 2018; 97:e11617. [PMID: 30045300 PMCID: PMC6078730 DOI: 10.1097/md.0000000000011617] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Acute myocardial infarction (AMI) is recognized as being a life-threatening event. Both microvascular obstruction (MVO) and intramyocardial hemorrhage (IMH) have been recognized as poor prognostic factors in myocardial infarct (MI) since they adversely affect left ventricular remodeling. MVO refers to small vessels changes that prevent adequate tissue perfusion despite revascularization whereas IMH is a severe form of MVO. A limited number of studies have demonstrated the segmental intervention time and the clinical factors in the presence of MVO and IMH. Therefore, we aimed in this study to determine the correlations of the intervention-associated and clinical indexes with malignant cardiovascular magnetic resonance (CMR) signs in patients with AMI.Sixty-three patients with STEMI who underwent primary percutaneous coronary intervention (PPCI) within 12 hours were included in this study. A 3.0-T CMR scan was prescribed, and the subsequent image analysis was conducted by researchers blinded to the clinical index results. Late-gadolinium enhancement (LGE) and T2* sequences were mainly used for MVO and IMH identification and quantification.Patients exhibiting both MVO and IMH had the highest level of LGE (P < .001) and were significantly more frequently assigned to a pre-PPCI thrombolysis in myocardial infarction (TIMI) flow class of 0 (n=25, 89.3%). The MVO size correlated positively with the IMH size (r = 0.81, P < .01). A pre-PPCI TIMI flow class of 0 was found to reliably predict the presence of IMH (P < .001). Patients who received the intervention 4 to 6 hours after MI onset were more likely to exhibit MVO and IMH, although this trend was not statistically significant.We showed in our study that both MVO and IMH correlated with the degree of AMI and the pre-PPCI coronary flow, and both tended to occur more frequently in cases involving an interval of 4 to 6 hours between the onset of MI and the intervention. CMR is a reliable method for assessing MVO and IMH and its imaging features following gadolinium administration are characteristic. These findings stress the importance of using CMR in evaluating and improving the outcome of the medical management.
Collapse
Affiliation(s)
- Min Ma
- Department of Cardiology, The Sixth People's Hospital of Chengdu
- Department of Cardiology
| | - Kai-yue Diao
- Department of Radiology, State Key Laboratory of Biotherapy, West China Hospital
| | - Zhi-gang Yang
- Department of Radiology, State Key Laboratory of Biotherapy, West China Hospital
| | | | - Ying-kun Guo
- Department of Radiology, Key Laboratory of Birth Defects and Related Diseases of Women and Children of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Meng-xi Yang
- Department of Radiology, Key Laboratory of Birth Defects and Related Diseases of Women and Children of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Yi Zhang
- Department of Radiology, State Key Laboratory of Biotherapy, West China Hospital
| | | |
Collapse
|
12
|
Yuan J, Usman A, Reid SA, King KF, Patterson AJ, Gillard JH, Graves MJ. Three-dimensional black-blood multi-contrast carotid imaging using compressed sensing: a repeatability study. MAGMA 2017; 31:183-190. [PMID: 28653214 PMCID: PMC5813054 DOI: 10.1007/s10334-017-0640-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 06/09/2017] [Accepted: 06/16/2017] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The purpose of this work is to evaluate the repeatability of a compressed sensing (CS) accelerated multi-contrast carotid protocol at 3 T. MATERIALS AND METHODS Twelve volunteers and eight patients with carotid disease were scanned on a 3 T MRI scanner using a CS accelerated 3-D black-blood multi-contrast protocol which comprises T 1w, T 2w and PDw without CS, and with a CS factor of 1.5 and 2.0. The volunteers were scanned twice, the lumen/wall area and wall thickness were measured for each scan. Eight patients were scanned once, the inter/intra-observer reproducibility of the measurements was calculated. RESULTS In the repeated volunteer scans, the interclass correlation coefficient (ICC) for the wall area measurement using a CS factor of 1.5 in PDw, T 1w and T 2w were 0.95, 0.81, and 0.97, respectively. The ICC for lumen area measurement using a CS factor of 1.5 in PDw, T 1w and T 2w were 0.96, 0.92, and 0.96, respectively. In patients, the ICC for inter/intra-observer measurements of lumen/wall area, and wall thickness were all above 0.81 in all sequences. CONCLUSION The results show a CS accelerated 3-D black-blood multi-contrast protocol is a robust and reproducible method for carotid imaging. Future protocol design could use CS to reduce the scanning time.
Collapse
Affiliation(s)
- Jianmin Yuan
- Department of Radiology, School of Clinical Medicine, University of Cambridge, Level 5, Box 218, Addenbrooke's Hospital, Hills Rd, Cambridge, CB2 0QQ, UK.
| | - Ammara Usman
- Department of Radiology, School of Clinical Medicine, University of Cambridge, Level 5, Box 218, Addenbrooke's Hospital, Hills Rd, Cambridge, CB2 0QQ, UK
| | | | | | - Andrew J Patterson
- Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Jonathan H Gillard
- Department of Radiology, School of Clinical Medicine, University of Cambridge, Level 5, Box 218, Addenbrooke's Hospital, Hills Rd, Cambridge, CB2 0QQ, UK
| | - Martin J Graves
- Department of Radiology, School of Clinical Medicine, University of Cambridge, Level 5, Box 218, Addenbrooke's Hospital, Hills Rd, Cambridge, CB2 0QQ, UK
- Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| |
Collapse
|
13
|
Yuan J, Makris G, Patterson A, Usman A, Das T, Priest A, Teng Z, Hilborne S, Prudencio D, Gillard J, Graves M. Relationship between carotid plaque surface morphology and perfusion: a 3D DCE-MRI study. MAGMA 2017; 31:191-199. [PMID: 28455630 PMCID: PMC5813060 DOI: 10.1007/s10334-017-0621-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 04/10/2017] [Accepted: 04/11/2017] [Indexed: 12/02/2022]
Abstract
Objective This study aims to explore the relationship between plaque surface morphology and neovascularization using a high temporal and spatial resolution 4D contrast-enhanced MRI/MRA sequence. Materials and methods Twenty one patients with either recent symptoms or a carotid artery stenosis ≥40% were recruited in this study. Plaque surface morphology and luminal stenosis were determined from the arterial phase MRA images. Carotid neovascularization was evaluated by a previously validated pharmacokinetic (PK) modeling approach. Ktrans (transfer constant) and vp (partial plasma volume) were calculated in both the adventitia and plaque. Results Image acquisition and analysis was successfully performed in 28 arteries. Mean luminal stenosis was 44% (range 11–82%). Both adventitial and plaque Ktrans in ulcerated/irregular plaques were significantly higher than smooth plaques (0.079 ± 0.018 vs. 0.064 ± 0.011 min−1, p = 0.02; 0.065 ± 0.013 vs. 0.055 ± 0.010 min−1, p = 0.03, respectively). Positive correlations between adventitial Ktrans and vp against stenosis were observed (r = 0.44, p = 0.02; r = 0.55, p = 0.01, respectively). Conclusion This study demonstrates the feasibility of using a single sequence to acquire both high resolution 4D CE-MRA and DCE-MRI to evaluate both plaque surface morphology and function. The results demonstrate significant relationships between lumen surface morphology and neovascularization.
Collapse
Affiliation(s)
- Jianmin Yuan
- Department of Radiology, University of Cambridge, Cambridge, UK.
| | - Gregory Makris
- Department of Radiology, University of Cambridge, Cambridge, UK
| | - Andrew Patterson
- Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Ammara Usman
- Department of Radiology, University of Cambridge, Cambridge, UK
| | - Tilak Das
- Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Andrew Priest
- Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Zhongzhao Teng
- Department of Radiology, University of Cambridge, Cambridge, UK
| | - Sarah Hilborne
- Department of Radiology, University of Cambridge, Cambridge, UK
| | - Dario Prudencio
- Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | | | - Martin Graves
- Department of Radiology, University of Cambridge, Cambridge, UK
- Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| |
Collapse
|
14
|
Wu X, Malhotra A, Forman HP, Nunez D, Sanelli P. The Use of High-Risk Criteria in Screening Patients for Blunt Cerebrovascular Injury: A Survey. Acad Radiol 2017; 24:456-461. [PMID: 27979639 DOI: 10.1016/j.acra.2016.11.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/01/2016] [Accepted: 11/02/2016] [Indexed: 11/17/2022]
Abstract
RATIONALE AND OBJECTIVES Blunt cerebrovascular injury (BCVI) is uncommon, but delayed detection can have disastrous consequences. The Denver criteria are the most commonly used screening criteria. We aim to examine the utilization of screening criteria in the emergency department (ED) of our institution and assess whether patients with risk factors were imaged. MATERIALS AND METHODS A survey questionnaire was sent out to radiologists in a large academic institution. A search was performed in the database on the use of CT angiography (CTA) and MR angiography (MRA) among patients with risk factors in the last 11 years. RESULTS The survey was sent to 173 radiologists, with 41 responses (35 complete). Most of the physicians (30 out of 35) surveyed selected CTA as their preferred modality to screen for BCVI, whereas the remaining physicians selected MRA. None of the respondents reported routine use of Denver screening criteria or grading scale in their readouts. Only five respondents selected risk factors in the Denver criteria correctly. In the institution search, among the 1331 patients with blunt trauma and risk factors for BCVI, 537 underwent at least one angiographic study (40.3%). There was an increase in the screening rate after February 2010 in all risk factors, but only statistically significant among patients with foramen transversarium fractures and C1-C3 fractures. CONCLUSIONS Both the Denver screening criteria and grading scale of vascular injury have been underutilized in the ED for patients with risk factors. Greater awareness and utilization of imaging can potentially result in decreased incidence of subsequent stroke in patients with blunt injury.
Collapse
Affiliation(s)
- Xiao Wu
- Yale School of Medicine, New Haven, Connecticut
| | - Ajay Malhotra
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, Box 208042, Tompkins East 2, 333 Cedar St, New Haven, CT 06520-8042.
| | - Howard P Forman
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut; Department of Economics, Yale School of Medicine, New Haven, Connecticut; Department of Management, Yale School of Medicine, New Haven, Connecticut; Department of Public Health, Yale School of Medicine, New Haven, Connecticut
| | - Diego Nunez
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut
| | - Pina Sanelli
- Department of Radiology, Northwell Health, Great Neck, New York
| |
Collapse
|
15
|
Kong L, Chen H, Yang Y, Chen L. A meta-analysis of arterial spin labelling perfusion values for the prediction of glioma grade. Clin Radiol 2016; 72:255-261. [PMID: 27932251 DOI: 10.1016/j.crad.2016.10.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 07/23/2016] [Accepted: 10/25/2016] [Indexed: 12/16/2022]
Abstract
AIM To investigate the ability of arterial spin labelling (ASL) perfusion parameters to distinguish high-grade from low-grade gliomas. MATERIALS AND METHODS The PubMed and EMBASE databases were systematically searched for relevant articles published up to September 2015. Studies that evaluated both high- and low-grade gliomas using ASL were included. The random effect model was used to calculate the standardised mean difference (SMD) of maximum mean absolute tumour blood flow values (aTBFmax, aTBFmean) and maximum mean relative tumour blood flow (rTBFmax, rTBFmean) between high- and low-grade gliomas. RESULTS Nine studies encompassing 305 patients with high- and low-grade gliomas, met all inclusion and exclusion criteria and were included in the study. Compared with low-grade gliomas, high-grade gliomas had a significant increase in all ASL perfusion values: aTBFmax (SMD=0.70, 95% confidence interval [CI]: 0.22-1.19, p=0.0046); aTBFmean (SMD=0.86, 95% CI: 0.2-1.52, p=0.01); rTBFmax (SMD=1.08, 95% CI: 0.54-1.63, p=0.0001) and rTBFmean (SMD=0.88, 95% CI: 0.35-1.4, p=0.0011). CONCLUSIONS The current study results indicate that tumour blood flow from ASL differs significantly with respect to the glioma grade. Despite some limitations, there is evidence that ASL may be useful to distinguish high- and low-grade gliomas. Further larger-scale studies are necessary to examine the utility of ASL to distinguish tumour grade.
Collapse
Affiliation(s)
- L Kong
- Department of Anesthesiology, Anhui Provincial Cancer Hospital, Hefei 230031, China
| | - H Chen
- Department of Anesthesiology, Nanjing General Hospital of Nanjing Military Command, Nanjing 210002, China
| | - Y Yang
- Department of Anesthesiology, Anhui Provincial Cancer Hospital, Hefei 230031, China
| | - L Chen
- Department of Anesthesiology, Anhui Provincial Cancer Hospital, Hefei 230031, China.
| |
Collapse
|
16
|
Lin YH, Lin HH, Liu HM, Lee CW, Chen YF. Diagnostic performance of CT and MRI on the detection of symptomatic intracranial dural arteriovenous fistula: a meta-analysis with indirect comparison. Neuroradiology 2016; 58:753-63. [PMID: 27185610 DOI: 10.1007/s00234-016-1696-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Accepted: 05/03/2016] [Indexed: 11/26/2022]
Abstract
INTRODUCTION This study aims to review the diagnostic performance of computed tomography (CT) and magnetic resonance imaging (MRI) in symptomatic dural arteriovenous fistula (DAVF). METHODS EMBASE, PubMed, and Cochrane Library were searched until April 2015 for studies which compared CT, MRI, or both with angiography for the detection of DAVF. The diagnostic performances of MRI and CT were indirectly compared using modality as a covariate in the analysis. RESULTS Thirteen studies met our inclusion criteria. MRI had a sensitivity of 0.90 (95 % confidence interval (CI) = 0.83-0.94) and specificity of 0.94 (95 % CI = 0.90-0.96). CT had a sensitivity of 0.80 (95 % CI = 0.62-0.90) and specificity of 0.87 (95 % CI = 0.74-0.94). MRI showed better diagnostic performance than CT (p = 0.02). Contrast medium use and time-resolved MR angiography did not improve MRI diagnostic performance (p = 0.31 and 0.44, respectively). CONCLUSION Both CT and MRI had good diagnostic performance. MRI was better than CT on the detection of symptomatic intracranial dural arteriovenous fistula in the indirect comparison.
Collapse
Affiliation(s)
- Yen-Heng Lin
- Institute of Epidemiology and Preventive Medicine, National Taiwan University, Taipei, Taiwan
- Department of Medical Imaging and Radiology, Hospital and Medical College, National Taiwan University Hospital in Taipei and Yuan-Lin Branch, 7, Chung-Shan South Road, Taipei, Taiwan, 10016
| | - Hsien-Ho Lin
- Institute of Epidemiology and Preventive Medicine, National Taiwan University, Taipei, Taiwan
| | - Hon-Man Liu
- Department of Medical Imaging and Radiology, Hospital and Medical College, National Taiwan University Hospital in Taipei and Yuan-Lin Branch, 7, Chung-Shan South Road, Taipei, Taiwan, 10016.
| | - Chung-Wei Lee
- Department of Medical Imaging and Radiology, Hospital and Medical College, National Taiwan University Hospital in Taipei and Yuan-Lin Branch, 7, Chung-Shan South Road, Taipei, Taiwan, 10016
| | - Ya-Fang Chen
- Department of Medical Imaging and Radiology, Hospital and Medical College, National Taiwan University Hospital in Taipei and Yuan-Lin Branch, 7, Chung-Shan South Road, Taipei, Taiwan, 10016
| |
Collapse
|
17
|
Ambrose N, Pierce IT, Gatehouse PD, Haskard DO, Firmin DN. Magnetic resonance imaging of vein wall thickness in patients with Behçet's syndrome. Clin Exp Rheumatol 2014; 32:S99-S102. [PMID: 25268665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 07/14/2014] [Indexed: 06/03/2023]
Abstract
OBJECTIVES Vascular disease is a serious complication of Behçet's syndrome (BS), occurring in up to 20% of subjects. Superficial thrombophlebitis, deep vein thrombosis, and arterial aneurysm formation are the most common manifestations. Venous thrombosis is thought to result from vessel wall inflammation. This work investigated the potential usefulness of high resolution magnetic resonance imaging (MRI) to identify inflammation in the venous walls in BS subjects. METHODS Seven healthy control (HC) subjects and five BS subjects were scanned with 3T MRI (Siemens Skyra). A standard MRI sequence was adapted for use in the venous system. Metronome guided breathing generated a regular respiratory variation of venous blood velocity. The vein wall imaging was triggered at an appropriate delay after the metronome. The popliteal vein was imaged. Vein wall images were ranked based on wall thickness and signal enhancement by two blinded, experienced observers. RESULTS Popliteal vein rank scores were found to be significantly increased in BS versus HC subjects by the first observer (p(Observer 1)=0.025, p(Observer2)=0.07) and also averaging both observers (p=0.05). The repeated images of each subject gave a degree of variability in results, potentially from drifting response to metronome guidance over the 10 minute scan. CONCLUSIONS MR imaging can detect increased vein wall thickness in BS subjects compared to healthy controls. Variable response to the metronome-guided breathing requires further development.
Collapse
Affiliation(s)
- Nicola Ambrose
- Cardiovascular Sciences, NHLI, Imperial College, London, UK.
| | | | | | | | | |
Collapse
|
18
|
Hilario A, Sepulveda JM, Perez-Nuñez A, Salvador E, Millan JM, Hernandez-Lain A, Rodriguez-Gonzalez V, Lagares A, Ramos A. A prognostic model based on preoperative MRI predicts overall survival in patients with diffuse gliomas. AJNR Am J Neuroradiol 2014; 35:1096-102. [PMID: 24457819 PMCID: PMC7965146 DOI: 10.3174/ajnr.a3837] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 11/10/2013] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Diffuse gliomas are classified as grades II-IV on the basis of histologic features, with prognosis determined mainly by clinical factors and histologic grade supported by molecular markers. Our aim was to evaluate, in patients with diffuse gliomas, the relationship of relative CBV and ADC values to overall survival. In addition, we also propose a prognostic model based on preoperative MR imaging findings that predicts survival independent of histopathology. MATERIALS AND METHODS We conducted a retrospective analysis of the preoperative diffusion and perfusion MR imaging in 126 histologically confirmed diffuse gliomas. Median relative CBV and ADC values were selected for quantitative analysis. Survival univariate analysis was made by constructing survival curves by using the Kaplan-Meier method and comparing subgroups by log-rank probability tests. A Cox regression model was made for multivariate analysis. RESULTS The study included 126 diffuse gliomas (median follow-up of 14.5 months). ADC and relative CBV values had a significant influence on overall survival. Median overall survival for patients with ADC < 0.799 × 10(-3) mm(2)/s was <1 year. Multivariate analysis revealed that patient age, relative CBV, and ADC values were associated with survival independent of pathology. The preoperative model provides greater ability to predict survival than that obtained by histologic grade alone. CONCLUSIONS ADC values had a better correlation with overall survival than relative CBV values. A preoperative prognostic model based on patient age, relative CBV, and ADC values predicted overall survival of patients with diffuse gliomas independent of pathology. This preoperative model provides a more accurate predictor of survival than histologic grade alone.
Collapse
Affiliation(s)
- A Hilario
- From the Departments of Radiology (A.H., A.R., E.S., J.M.M.)
| | | | - A Perez-Nuñez
- Neurosurgery (A.P.-N., A.L.), Hospital 12 de Octubre, Madrid, Spain
| | - E Salvador
- From the Departments of Radiology (A.H., A.R., E.S., J.M.M.)
| | - J M Millan
- From the Departments of Radiology (A.H., A.R., E.S., J.M.M.)
| | | | | | - A Lagares
- Neurosurgery (A.P.-N., A.L.), Hospital 12 de Octubre, Madrid, Spain
| | - A Ramos
- From the Departments of Radiology (A.H., A.R., E.S., J.M.M.)
| |
Collapse
|
19
|
Sulik VV. [Algorithm for the diagnosis of the vertebral artery compression syndrome based on sensitivity of ultrasound and angiographic methods]. Lik Sprava 2014:55-60. [PMID: 25286599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The results of sensitivity analysis and ultrasonic techniques hagiographic 150 patients with vertebral artery syndrome caused by compression extravasal (ECVA) segment V(p), who underwent surgery on clinical. In assessing the sensitivity by a static cross-vertebral artery, vessel diameter, the condition of the lumen--Ultrasonic and hagiographic (SAG and MRA) techniques showed the same high sensitivity in the range 85-89% (P > 0.05), and according to such criteria as the dynamic permeability (89.2% vs. 34.2 and 45.5%), the value of ripple vascular (86.3% vs. 58 and 67%), the state of the perivascular tissue USDG figures were significantly higher than the data angiography (82.2% vs. 0 and 29%) (P < 0.05 for all tests). Comparative analysis of selective angiography, enhanced magnetic resonance angiography and ultrasound proposed method allowed us to determine their sensitivity. Thus, the sensitivity of selective angiography in extravasal vertebral artery compression is 57.1%, magnetic resonance angiography--88% and triplex ultrasound-- 91.3%.
Collapse
|
20
|
Gutierrez J, Rundek T, Ekind MSV, Sacco RL, Wright CB. Perivascular spaces are associated with atherosclerosis: an insight from the Northern Manhattan Study. AJNR Am J Neuroradiol 2013; 34:1711-6. [PMID: 23557952 DOI: 10.3174/ajnr.a3498] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Perivascular spaces are potential spaces found between brain blood vessels and surrounding leptomeninges that have been associated with cardiovascular risk factors and dementia, but less is known about their relationship to atherosclerosis. We tested the hypothesis that perivascular spaces are associated with atherosclerosis. MATERIALS AND METHODS Participants from the Northern Manhattan Study who remained stroke-free were invited to participate in an MR imaging substudy. Parenchymal hypointensities of <3 mm identified on brain axial T1-weighted MR imaging were scored as perivascular spaces. A semiquantitative score was created to express the degree of brain involvement. Generalized linear models were used to assess statistical associations with carotid plaque as a surrogate marker of atherosclerosis. RESULTS The studied sample included 706 participants (mean age, 72.6 ± 8.0 years; 60% women, 61% Hispanic, 68% with hypertension, 19% with diabetes, and 57% with high cholesterol). The perivascular spaces score ranged from 0 to 19 with 52% of the sample having a perivascular spaces score of ≤4. In unadjusted analysis, perivascular spaces were associated with age (β = 0.01 per year, P = < .001), non-Hispanic black race-ethnicity (β = 0.16, P = .02), hypertension (β = 0.24, P = < .001), and carotid plaque (β = 0.22, P < .001). In multivariable analysis, only age (β = 0.01, P = .02), hypertension (β = 0.17, P = .01), and carotid plaque (β = 0.22, P = < .001) remained independently associated with perivascular spaces. CONCLUSIONS Perivascular spaces were more frequently found in older participants, in those with hypertension, and in the presence of carotid plaque. These results suggest that mechanisms leading to atherosclerosis might also lead to an increased number of perivascular spaces. These results need confirmation in prospective studies.
Collapse
Affiliation(s)
- J Gutierrez
- Department of Neurology, College of Physicians and Surgeons
| | | | | | | | | |
Collapse
|
21
|
Niemczyk M, Gradzik M, Niemczyk S, Bujko M, Gołębiowski M, Pączek L. Intracranial aneurysms in autosomal dominant polycystic kidney disease. AJNR Am J Neuroradiol 2013; 34:1556-9. [PMID: 23449651 DOI: 10.3174/ajnr.a3456] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND PURPOSE ADPKD correlates with an increased frequency of ICANs, but universal screening for ICANs in patients with ADPKD is not currently recommended. The aim of our study was to determine which groups might benefit from screening by determining the prevalence of ICANs in the Polish ADPKD population and identifying any subgroups with an increased risk for ICANs. MATERIALS AND METHODS Eighty-three adult, predialysis-phase patients with ADPKD underwent screening for ICANs with MRA of the brain. RESULTS The prevalence of ICANs in the studied population was 16.9%, with 6% of the screened group requiring neurosurgical intervention. We also found that the frequency of ICANs increases with age, reaching 22.4% in patients older than 45 years. All diagnosed ICANs were small (< 9 mm) and were localized in the anterior circulation. In addition, MR imaging revealed arachnoid cysts in 4.8% of patients with ADPKD. CONCLUSIONS We suggest that patients older than 45 years with ADPKD be considered as candidates for screening for ICANs, and we propose a clinical algorithm for this subgroup. However, we could not find risk factors for ICANs in younger patients with ADPKD.
Collapse
Affiliation(s)
- M Niemczyk
- Department of Immunology, Transplant Medicine, and Internal Diseases, Medical University of Warsaw, Warsaw, Poland.
| | | | | | | | | | | |
Collapse
|
22
|
Affiliation(s)
- J P Klein
- Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| |
Collapse
|
23
|
Ota H, Reeves MJ, Zhu DC, Majid A, Collar A, Yuan C, DeMarco JK. Sex differences of high-risk carotid atherosclerotic plaque with less than 50% stenosis in asymptomatic patients: an in vivo 3T MRI study. AJNR Am J Neuroradiol 2013. [PMID: 23194832 DOI: 10.3174/ajnr.a3399] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND AND PURPOSE Men have a greater prevalence of high-risk carotid plaque features associated with stroke compared with women who have ≥50% stenosis, but little is known about these features in less significantly stenotic carotid arteries. This study aims to evaluate sex differences in complicated carotid plaque features in asymptomatic patients with <50% stenosis. MATERIALS AND METHODS Ninety-six patients (50 men, 46 women) with <50% carotid stenosis on MRA who had been referred for analysis of contralateral >50% carotid stenosis were included. The associations between sex and plaque features as identified by 3T MR carotid plaque imaging were examined by using logistic and linear regression models controlling for demographic characteristics, MRA stenosis, and the presence of contralateral plaque features. RESULTS The presence of a thin/ruptured fibrous cap (16% versus 2%, adjusted odds ratio = 8.57, P = .047), IPH (24% versus 6%, adjusted odds ratio = 4.53, P = .027), and American Heart Association type VI plaque (26% versus 6%, adjusted odds ratio = 5.04, P = .017) was significantly higher in men than in women. These associations remained significant following adjustment for contralateral plaque features. Men demonstrated a larger percentage volume of LR/NC (median, 1.66% versus -0.21%; P < .01). Calcification was not significantly associated with sex. CONCLUSIONS There is a sex difference of higher risk carotid plaque features during the early stage of disease seen in patients recruited for MR imaging evaluation of contralateral moderate-to-severe stenosis. Given the potential of using LR/NC without or with IPH to monitor therapy, these results indicate the possible importance of sex-based management in patients with asymptomatic carotid atherosclerosis across all stages of carotid stenosis.
Collapse
Affiliation(s)
- H Ota
- Department of Radiology, Michigan State University, East Lansing, Michigan 48824-1303, USA
| | | | | | | | | | | | | |
Collapse
|
24
|
Ssi-Yan-Kai G, Nasr N, Faury A, Catalaa I, Cognard C, Larrue V, Bonneville F. Intracranial artery stenosis or occlusion predicts ischemic recurrence after transient ischemic attack. AJNR Am J Neuroradiol 2013; 34:185-90. [PMID: 22678847 DOI: 10.3174/ajnr.a3144] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Patterns of DWI findings that predict recurrent ischemic events after TIA are well-established, but similar assessments of intracranial MRA findings are not available. We sought to determine the imaging characteristics of MRA that are predictive of early recurrent stroke/TIA in patients with TIA. MATERIALS AND METHODS We performed a retrospective analysis of 129 consecutive patients with a clinical diagnosis of TIA in whom MR imaging was done within 24 hours of symptom onset. We calculated the sensitivity, specificity, positive predictive value, and negative predictive value of >50% stenosis or occlusion of symptomatic intracranial arteries for recurrent stroke/TIA at 7 days after TIA. We used logistic regression analysis to adjust for the clinical ABCD(2) score. We performed this analysis for symptomatic steno-occlusive lesions at any site and symptomatic steno-occlusive lesions on proximal large intracranial arteries (internal carotid artery, vertebral artery, basilar artery, and circle of Willis). RESULTS Forty-two (32.5%) patients had acute ischemic lesions on DWI; 16 (12.4%) had significant MRA lesions, of which 11 (8.5%) were on proximal vessels. Nine patients had early recurrence (TIA, 7; minor stroke, 2). Only patients with proximal MRA lesions were at higher risk of early recurrence independent of the ABCD(2) score (adjusted odds ratio, 5.5; 95% confidence interval, 1.1-27.8; P = .04). CONCLUSIONS Proximal lesions of cerebral arteries seen on MRA were predictive of recurrent stroke/TIA at 7 days. These findings suggest that MRA could be used to improve the selection of patients with TIA at high risk of early recurrent stroke/TIA.
Collapse
Affiliation(s)
- G Ssi-Yan-Kai
- Department of Neuroradiology, University of Toulouse, Toulouse. France
| | | | | | | | | | | | | |
Collapse
|
25
|
Abstract
Flows through tubular structures are common in many fields, including blood flow in medicine and tubular fluid flows in engineering. The analysis of such flows is often done with a strong reference to the main flow direction along the tubular boundary. In this paper we present an approach for straightening the visualization of tubular flow. By aligning the main reference direction of the flow, i.e., the center line of the bounding tubular structure, with one axis of the screen, we are able to natively juxtapose (1.) different visualizations of the same flow, either utilizing different flow visualization techniques, or by varying parameters of a chosen approach such as the choice of seeding locations for integration-based flow visualization, (2.) the different time steps of a time-dependent flow, (3.) different projections around the center line , and (4.) quantitative flow visualizations in immediate spatial relation to the more qualitative classical flow visualization. We describe how to utilize this approach for an informative interactive visual analysis. We demonstrate the potential of our approach by visualizing two datasets from two different fields: an arterial blood flow measurement and a tubular gas flow simulation from the automotive industry.
Collapse
|
26
|
van Pelt R, Bescós JO, Breeuwer M, Clough RE, Gröller ME, Romenij BTH, Vilanova A. Interactive virtual probing of 4D MRI blood-flow. IEEE Trans Vis Comput Graph 2011; 17:2153-2162. [PMID: 22034334 DOI: 10.1109/tvcg.2011.215] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Better understanding of hemodynamics conceivably leads to improved diagnosis and prognosis of cardiovascular diseases. Therefore, an elaborate analysis of the blood-flow in heart and thoracic arteries is essential. Contemporary MRI techniques enable acquisition of quantitative time-resolved flow information, resulting in 4D velocity fields that capture the blood-flow behavior. Visual exploration of these fields provides comprehensive insight into the unsteady blood-flow behavior, and precedes a quantitative analysis of additional blood-flow parameters. The complete inspection requires accurate segmentation of anatomical structures, encompassing a time-consuming and hard-to-automate process, especially for malformed morphologies. We present a way to avoid the laborious segmentation process in case of qualitative inspection, by introducing an interactive virtual probe. This probe is positioned semi-automatically within the blood-flow field, and serves as a navigational object for visual exploration. The difficult task of determining position and orientation along the view-direction is automated by a fitting approach, aligning the probe with the orientations of the velocity field. The aligned probe provides an interactive seeding basis for various flow visualization approaches. We demonstrate illustration-inspired particles, integral lines and integral surfaces, conveying distinct characteristics of the unsteady blood-flow. Lastly, we present the results of an evaluation with domain experts, valuing the practical use of our probe and flow visualization techniques.
Collapse
Affiliation(s)
- Roy van Pelt
- Department of Biomedical Engineering, within the group of Biomedical Image Analysis, Eindhoven University of Technology.
| | | | | | | | | | | | | |
Collapse
|
27
|
Blinov NN, Vasil'ev AI, Zinchenko VI. [The necessity and sufficiency of technical upgrade of domestic healthcare service]. Med Tekh 2011:26-29. [PMID: 22145400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
|
28
|
Lee K, Kim H, Heo JH, Bae HJ, Koh IS, Chang S. Application of magnetic resonance imaging and magnetic resonance angiography as diagnostic measures for the first attack of suspected cerebrovascular diseases in Korea. Yonsei Med J 2011; 52:727-33. [PMID: 21786435 PMCID: PMC3159928 DOI: 10.3349/ymj.2011.52.5.727] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE No precise data are available showing how magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) can be applied to diagnosis for the first attack of a suspected cerebrovascular disease in Korea. The purpose of this study was to evaluate the application level of MRI and MRA as diagnostic tools and the related factors to the use of these techniques. MATERIALS AND METHODS This study used the health benefit claim data of 89,890 patients who were hospitalized for the first time due to suspected cerebrovascular disease in 2007 without having visited medical institutions as an outpatient or inpatient from 2003 to 2006. RESULTS Of the 89,890 cases, 28.4% took both MRI and MRA, 10.7% took only MRI and 6.9% took only MRA. The related factors identified in the multivariate logistic regression analysis were gender, type of insurance, type of medical institution, type of department, duration of hospitalization, and type of disease. CONCLUSION This study showed that the application level of MRI and MRA as diagnostic measures for the first attack of a suspected cerebrovascular diseases varied depending on several factors. It is necessary to study more accurate levels of computerized tomography (CT), computerized tomography angiography (CTA), MRI or MRA as measures to diagnose a first attack of suspected cerebrovascular disease.
Collapse
Affiliation(s)
- Kunsei Lee
- Department of Preventive Medicine, School of Medicine, Konkuk University, Seoul, Korea
| | - Hyeongsu Kim
- Department of Preventive Medicine, School of Medicine, Konkuk University, Seoul, Korea
| | - Jae-Hyeok Heo
- Department of Neurology, Seoul Medical Center, Seoul, Korea
| | - Hee-Joon Bae
- Department of Neurology, Seoul National University Bundang Hospital, College of Medicine, Seoul National University, Seongnam, Korea
| | - Im-Seok Koh
- Department of Neurology, National Medical Center, Seoul, Korea
| | - Sounghoon Chang
- Department of Preventive Medicine, School of Medicine, Konkuk University, Seoul, Korea
| |
Collapse
|
29
|
van Pelt R, Oliván Bescós J, Breeuwer M, Clough RE, Gröller ME, ter Haar Romenij B, Vilanova A. Exploration of 4D MRI blood flow using stylistic visualization. IEEE Trans Vis Comput Graph 2010; 16:1339-1347. [PMID: 20975174 DOI: 10.1109/tvcg.2010.153] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Insight into the dynamics of blood-flow considerably improves the understanding of the complex cardiovascular system and its pathologies. Advances in MRI technology enable acquisition of 4D blood-flow data, providing quantitative blood-flow velocities over time. The currently typical slice-by-slice analysis requires a full mental reconstruction of the unsteady blood-flow field, which is a tedious and highly challenging task, even for skilled physicians. We endeavor to alleviate this task by means of comprehensive visualization and interaction techniques. In this paper we present a framework for pre-clinical cardiovascular research, providing tools to both interactively explore the 4D blood-flow data and depict the essential blood-flow characteristics. The framework encompasses a variety of visualization styles, comprising illustrative techniques as well as improved methods from the established field of flow visualization. Each of the incorporated styles, including exploded planar reformats, flow-direction highlights, and arrow-trails, locally captures the blood-flow dynamics and may be initiated by an interactively probed vessel cross-section. Additionally, we present the results of an evaluation with domain experts, measuring the value of each of the visualization styles and related rendering parameters.
Collapse
|
30
|
Raoult H, Ferré JC, Morandi X, Carsin-Nicol B, Carsin M, Cuggia M, Law M, Gauvrit JY. Quality-evaluation scheme for cerebral time-resolved 3D contrast-enhanced MR angiography techniques. AJNR Am J Neuroradiol 2010; 31:1480-7. [PMID: 20448014 DOI: 10.3174/ajnr.a2093] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE No practical tool has been reported in the literature to evaluate the quality of cerebral TR-3D-CE-MRA techniques. Our study assessed a large list of parameters used to propose a quality-evaluation scheme for TR-3D-CE-MRA. MATERIALS AND METHODS A large list of visual and quantitative parameters used to study the quality of images was collected from the literature and evaluated in 19 healthy patients and 11 patients with arteriovenous shunts who had undergone both CENTRA keyhole TR-3D-CE-MRA at 3T and CCA. Several observers evaluated the visual parameters, such as the diagnostic confidence index, artifacts, maximum vascular signal intensity, arterial-to-venous separation, and visibility of 17 arteries and 7 veins; and quantitative parameters, such as maximum arterial SI, arteriovenous transit time, arteriovenous contrast curve, and ADW. A statistical analysis was used to determine interobserver reproducibility of the visual parameters, to calculate the sensitivity of TR-3D-CE-MRA for detecting each vessel (with CCA as standard of reference), and to compare the results of the visual and quantitative evaluations. RESULTS Diagnostic confidence index, artifacts, arterial-to-venous separation, and 4 vessels-the PICA, ophthalmic and occipital arteries, and the ISS-demonstrated high reproducibility and sensitivity. The ADW was the most reliable dynamic quantitative parameter and was correlated with arterial-to-venous separation. CONCLUSIONS The image quality of TR-3D-CE-MRA can be effectively evaluated with a scheme of 1 quantitative and 7 visual parameters.
Collapse
Affiliation(s)
- H Raoult
- Department of Neuroradiology, Pontchaillou University Hospital, Rennes, France
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Kim J, Leira EC, Callison RC, Ludwig B, Moritani T, Magnotta VA, Madsen MT. Toward fully automated processing of dynamic susceptibility contrast perfusion MRI for acute ischemic cerebral stroke. Comput Methods Programs Biomed 2010; 98:204-213. [PMID: 20060614 DOI: 10.1016/j.cmpb.2009.12.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2009] [Revised: 12/14/2009] [Accepted: 12/15/2009] [Indexed: 05/28/2023]
Abstract
We developed fully automated software for dynamic susceptibility contrast (DSC) MR perfusion-weighted imaging (PWI) to efficiently and reliably derive critical hemodynamic information for acute stroke treatment decisions. Brain MR PWI was performed in 80 consecutive patients with acute nonlacunar ischemic stroke within 24h after onset of symptom from January 2008 to August 2009. These studies were automatically processed to generate hemodynamic parameters that included cerebral blood flow and cerebral blood volume, and the mean transit time (MTT). To develop reliable software for PWI analysis, we used computationally robust algorithms including the piecewise continuous regression method to determine bolus arrival time (BAT), log-linear curve fitting, arrival time independent deconvolution method and sophisticated motion correction methods. An optimal arterial input function (AIF) search algorithm using a new artery-likelihood metric was also developed. Anatomical locations of the automatically determined AIF were reviewed and validated. The automatically computed BAT values were statistically compared with estimated BAT by a single observer. In addition, gamma-variate curve-fitting errors of AIF and inter-subject variability of AIFs were analyzed. Lastly, two observes independently assessed the quality and area of hypoperfusion mismatched with restricted diffusion area from motion corrected MTT maps and compared that with time-to-peak (TTP) maps using the standard approach. The AIF was identified within an arterial branch and enhanced areas of perfusion deficit were visualized in all evaluated cases. Total processing time was 10.9+/-2.5s (mean+/-s.d.) without motion correction and 267+/-80s (mean+/-s.d.) with motion correction on a standard personal computer. The MTT map produced with our software adequately estimated brain areas with perfusion deficit and was significantly less affected by random noise of the PWI when compared with the TTP map. Results of image quality assessment by two observers revealed that the MTT maps exhibited superior quality over the TTP maps (88% good rating of MTT as compared to 68% of TTP). Our software allowed fully automated deconvolution analysis of DSC PWI using proven efficient algorithms that can be applied to acute stroke treatment decisions. Our streamlined method also offers promise for further development of automated quantitative analysis of the ischemic penumbra.
Collapse
Affiliation(s)
- Jinsuh Kim
- Department of Radiology, University of Iowa, 200 Hawkins Dr., Iowa City, IA 52242, USA
| | | | | | | | | | | | | |
Collapse
|
32
|
Pan Y, Gao J, Haber M, Barnhart HX. Estimation of coefficients of individual agreement (CIAs) for quantitative and binary data using SAS and R. Comput Methods Programs Biomed 2010; 98:214-219. [PMID: 20079947 PMCID: PMC2856751 DOI: 10.1016/j.cmpb.2009.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 09/11/2009] [Accepted: 12/06/2009] [Indexed: 05/28/2023]
Abstract
The coefficients of individual agreement (CIAs), which are based on the ratio of the intra- and inter-observer disagreement, provide a general approach for evaluating agreement between two fixed methods of measurements or human observers. In this paper, programs in both SAS and R are presented for estimation of the CIAs between two observers with quantitative or binary measurements. A detailed illustration of the computations, macro variable definitions, input and output for the SAS and R programs are also included in the text. The programs provide estimations of CIAs, their standard errors as well as confidence intervals, for the cases with or without a reference method. Data from a carotid stenosis screening study is used as an example of quantitative measurements. Data from a study involving the evaluation of mammograms by ten radiologists is used to illustrate a binary data example.
Collapse
Affiliation(s)
- Yi Pan
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, 1518 Clifton Road NE, Atlanta, GA 30322, United States
| | | | | | | |
Collapse
|
33
|
Wasserman BA, Astor BC, Sharrett AR, Swingen C, Catellier D. MRI measurements of carotid plaque in the atherosclerosis risk in communities (ARIC) study: methods, reliability and descriptive statistics. J Magn Reson Imaging 2010; 31:406-15. [PMID: 20099354 DOI: 10.1002/jmri.22043] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To measure carotid plaque components using MRI and estimate reliability in the population-based Atherosclerosis Risk in Communities (ARIC) study. MATERIALS AND METHODS Contrast-enhanced high-resolution (0.51 x 0.58 x 2 mm(3)) MRI images were acquired through internal (ICA) and common carotid arteries (CCA) of 2066 ARIC participants at four sites. Sixty-one exams were repeated and 164 pairs had repeated interpretations. Plaque component thicknesses, areas and volumes over eight slices (1.6-cm segment) were measured. Intraplaque hemorrhage was recorded. Reliability was evaluated by intraclass correlations and kappa statistics. RESULTS There were 1769 successful MRI exams (mean age 71 years; 57% females; 81% white; 19% African-Americans). Repeat scan reliability was highest for CCA lumen area (0.94) and maximum wall thickness (0.89), ICA lumen area (0.89) and maximum wall thickness (0.77) and total wall volume (0.79), and lowest for small structures-core volume (0.30) and mean cap thickness (0.38). Overall reliability was primarily related to reader variability rather than scan acquisition. K's for presence of core, calcification and hemorrhage were fair to good. White men had the thickest plaques (average maximum ICA wall thickness = 2.3 mm) and the most cores (34%). CONCLUSION The most important limiting factor for MRI measurements of plaque components is reader variability. Measurement error depends largely on the analyzed structure's size.
Collapse
Affiliation(s)
- Bruce A Wasserman
- The Russell H. Morgan Department of Radiology and Radiological Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | | | | | | | | |
Collapse
|
34
|
Abstract
Arterial spin labeling (ASL) perfusion magnetic resonance imaging has gained wide acceptance for its value in clinical and neuroscience applications during recent years. Its capability for noninvasive and absolute perfusion quantification is a key characteristic that makes ASL attractive for many clinical applications. In the present review, we discuss the main parameters or factors that affect the reliability and accuracy of ASL perfusion measurements. Our secondary goal was to outline potential solutions that may improve the reliability and accuracy of ASL in clinical settings. It was found that, through theoretical analyses, flow quantification is most sensitive to tagging efficiency and estimation of the equilibrium magnetization of blood signal (M(0b)). Variations of blood T1 have a greater effect on perfusion quantification than variations of tissue T1. Arterial transit time becomes an influential factor when it is longer than the postlabeling delay time. The T2's of blood and tissue impose minimal effects on perfusion calculation at field strengths equal to or lower than 3.0 T. Subsequently, we proposed various approaches for in vivo estimation or calibration of the above parameters, such as the use of phase-contrast magnetic resonance imaging for calibration of the labeling efficiency as well as the use of inversion recovery TrueFISP (true fast imaging with steady-state precession) sequence for blood T1 mapping. We also list representative clinical cases in which implicit assumptions for ASL perfusion quantification may be violated, such as the venous outflow effect in children with sickle cell disease. Finally, an optimal imaging protocol including in vivo measurements of several critical parameters was recommended for clinical ASL studies.
Collapse
Affiliation(s)
- Wen-Chau Wu
- Graduate Institute of Oncology and Graduate Institute of Clinical Medicine, National Taiwan University, Taipei, Taiwan
| | | | | | | |
Collapse
|
35
|
Kilner PJ, Geva T, Kaemmerer H, Trindade PT, Schwitter J, Webb GD. Recommendations for cardiovascular magnetic resonance in adults with congenital heart disease from the respective working groups of the European Society of Cardiology. Eur Heart J 2010; 31:794-805. [PMID: 20067914 PMCID: PMC2848324 DOI: 10.1093/eurheartj/ehp586] [Citation(s) in RCA: 275] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Revised: 11/09/2009] [Accepted: 12/07/2009] [Indexed: 11/12/2022] Open
Abstract
This paper aims to provide information and explanations regarding the clinically relevant options, strengths, and limitations of cardiovascular magnetic resonance (CMR) in relation to adults with congenital heart disease (CHD). Cardiovascular magnetic resonance can provide assessments of anatomical connections, biventricular function, myocardial viability, measurements of flow, angiography, and more, without ionizing radiation. It should be regarded as a necessary facility in a centre specializing in the care of adults with CHD. Also, those using CMR to investigate acquired heart disease should be able to recognize and evaluate previously unsuspected CHD such as septal defects, anomalously connected pulmonary veins, or double-chambered right ventricle. To realize its full potential and to avoid pitfalls, however, CMR of CHD requires training and experience. Appropriate pathophysiological understanding is needed to evaluate cardiovascular function after surgery for tetralogy of Fallot, transposition of the great arteries, and after Fontan operations. For these and other complex CHD, CMR should be undertaken by specialists committed to long-term collaboration with the clinicians and surgeons managing the patients. We provide a table of CMR acquisition protocols in relation to CHD categories as a guide towards appropriate use of this uniquely versatile imaging modality.
Collapse
|
36
|
Gao H, Long Q, Graves M, Gillard JH, Li ZY. Carotid arterial plaque stress analysis using fluid-structure interactive simulation based on in-vivo magnetic resonance images of four patients. J Biomech 2009; 42:1416-1423. [PMID: 19464011 DOI: 10.1016/j.jbiomech.2009.04.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Revised: 04/06/2009] [Accepted: 04/06/2009] [Indexed: 11/18/2022]
Abstract
The rupture of atherosclerotic plaques is known to be associated with the stresses that act on or within the arterial wall. The extreme wall tensile stress (WTS) is usually recognized as a primary trigger for the rupture of vulnerable plaque. The present study used the in-vivo high-resolution multi-spectral magnetic resonance imaging (MRI) for carotid arterial plaque morphology reconstruction. Image segmentation of different plaque components was based on the multi-spectral MRI and co-registered with different sequences for the patient. Stress analysis was performed on totally four subjects with different plaque burden by fluid-structure interaction (FSI) simulations. Wall shear stress distributions are highly related to the degree of stenosis, while the level of its magnitude is much lower than the WTS in the fibrous cap. WTS is higher in the luminal wall and lower at the outer wall, with the lowest stress at the lipid region. Local stress concentrations are well confined in the thinner fibrous cap region, and usually locating in the plaque shoulder; the introduction of relative stress variation during a cycle in the fibrous cap can be a potential indicator for plaque fatigue process in the thin fibrous cap. According to stress analysis of the four subjects, a risk assessment in terms of mechanical factors could be made, which may be helpful in clinical practice. However, more subjects with patient specific analysis are desirable for plaque-stability study.
Collapse
Affiliation(s)
- Hao Gao
- Brunel Institute for Bioengineering, Brunel University, Uxbridge, Middlesex UB8 3PH, UK
| | - Quan Long
- Brunel Institute for Bioengineering, Brunel University, Uxbridge, Middlesex UB8 3PH, UK.
| | - Martin Graves
- University Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge CB2 0QQ, UK
| | - Jonathan H Gillard
- University Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge CB2 0QQ, UK
| | - Zhi-Yong Li
- University Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge CB2 0QQ, UK
| |
Collapse
|
37
|
Babiarz LS, Romero JM, Murphy EK, Brobeck B, Schaefer PW, González RG, Lev MH. Contrast-enhanced MR angiography is not more accurate than unenhanced 2D time-of-flight MR angiography for determining > or = 70% internal carotid artery stenosis. AJNR Am J Neuroradiol 2009; 30:761-8. [PMID: 19164440 DOI: 10.3174/ajnr.a1464] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND PURPOSE Internal carotid artery (ICA) atheromatous disease is an important cause of ischemic stroke, and endarterectomy or stent placement is typically indicated for symptomatic patients with > or = 70% stenosis. Our purpose was to compare contrast-enhanced MR angiography (CE-MRA) with unenhanced 2D time-of-flight MR angiography (2D TOF MRA) in detecting hemodynamically significant ICA stenosis, by using CT angiography (CTA) as the reference standard. MATERIALS AND METHODS This was an institutional review board-approved retrospective study. We identified 177 consecutive patients (354 ICAs) who received correlative CE-MRA, 2D TOF MRA, and CTA. Two neuroradiologists blinded to the CTA data graded the degree of ICA stenosis according to a 5-point scale. Additionally, luminal signal-intensity characteristics including 1) signal intensity drop-out, 2) distal-vessel narrowing, and 3) distal-vessel signal-intensity reduction were recorded. MRA results were correlated with those of CTA, and receiver-operating-characteristic (ROC) curves were constructed. RESULTS On CTA, there were 55 ICAs with and 299 without > or = 70% stenosis. CE-MRA was 84% sensitive and 96% specific for detecting > or = 70% stenosis; 2D TOF MRA was 80% sensitive and 95% specific. The area under the ROC curve was 0.97 for CE-MRA and 0.95 for 2D TOF MRA (P = .51, not significant). For both MRA studies, each of the luminal signal-intensity characteristics had high specificity (> 98%) but poor-to-mild sensitivity (35%-66%) in detecting > or = 70% stenosis. CONCLUSIONS Although it is established that CE-MRA more accurately delineates neurovascular anatomy than does unenhanced 2D TOF MRA, the administration of gadolinium did not offer a significant advantage in distinguishing surgically treatable ICA stenosis. This conclusion may be important in patients with contraindications to gadolinium.
Collapse
Affiliation(s)
- L S Babiarz
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Mass. 02114, USA
| | | | | | | | | | | | | |
Collapse
|
38
|
Díaz Aguilera R, Bravo Rodríguez F, Ramos Gómez MJ, Cano Sánchez A, Martínez Paredes M, Delgado Acosta F. [MR angiography follow-up of embolized cerebral aneurysms: interobserver agreement]. Radiologia 2009; 51:300-6. [PMID: 19282007 DOI: 10.1016/j.rx.2008.11.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Accepted: 06/24/2008] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To determine the interobserver agreement in the interpretation of MR angiography (MRA) studies for surveillance of embolized intracranial aneurysms. To determine whether contrast administration improves interobserver agreement. MATERIAL AND METHODS Two experienced neuroradiologists independently reviewed all follow-up MRA studies performed between July 2004 and December 2006 of cerebral aneurysms embolized with coils. All MRA studies included both unenhanced 3D time-of-flight (3D TOF) and contrast-enhanced MRA (CE-MRA) images. Studies were classified as: a) not assessable; b) complete occlusion; c) residual aneurysm. Interobserver agreement for unenhanced and enhanced MRA studies was determined using the kappa statistic. Kappa values were considered insignificant when<0.2, low when between 0.21 and 0.4, and moderate when between 0.41-0.6; values >0.6 were considered good agreement and >0.8 excellent agreement. Significance was set at p<0.005. RESULTS We reviewed a total of 200 MRA studies (100 3D TOF studies and 100 CE-MRA studies) performed in 48 patients (25 women, 23 men) at 6, 12, and/or 24 months after embolization. Interobserver agreement was good in both 3D TOF and CE-MRA studies, although it was better in CE-MRA studies (kappa=0.660, p<0.001 and kappa=0.779, p<0.001, respectively). CONCLUSIONS Interobserver agreement is good for follow-up MRA studies of embolized intracranial aneurysms. Gadolinium administration improves interobserver agreement.
Collapse
Affiliation(s)
- R Díaz Aguilera
- Sección de Neurorradiología, Servicio de Radiodiagnóstico, Hospital Universitario Reina Sofía, Córdoba, España.
| | | | | | | | | | | |
Collapse
|
39
|
Py MO, André C. Accuracy of magnetic resonance angiography for internal carotid artery disease. Stroke 2008; 40:e1; author reply e2. [PMID: 19038909 DOI: 10.1161/strokeaha.108.536177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
40
|
Stein PD, Gottschalk A, Sostman HD, Chenevert TL, Fowler SE, Goodman LR, Hales CA, Hull RD, Kanal E, Leeper KV, Nadich DP, Sak DJ, Tapson VF, Wakefield TW, Weg JG, Woodard PK. Methods of Prospective Investigation of Pulmonary Embolism Diagnosis III (PIOPED III). Semin Nucl Med 2008; 38:462-70. [PMID: 19331840 PMCID: PMC2605689 DOI: 10.1053/j.semnuclmed.2008.06.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In this work, the methods of the Prospective Investigation of Pulmonary Embolism Diagnosis III (PIOPED III) are described in detail. PIOPED III is a multicenter collaborative investigation sponsored by the National Heart, Lung and Blood Institute. The purpose is to determine the accuracy of gadolinium-enhanced magnetic resonance angiography in combination with venous phase magnetic resonance venography for the diagnosis of acute pulmonary embolism (PE). A composite reference standard based on usual diagnostic methods for PE is used. All images will be read by 2 blinded and study-certified central readers. Patients with no PE according to the composite reference test will be randomized to undergo gadolinium-enhanced magnetic resonance angiography in combination with venous phase magnetic resonance venography. This procedure will reduce the proportion of patients with negative tests at no loss in evaluation of sensitivity and specificity.
Collapse
Affiliation(s)
- Paul D Stein
- Department of Research, St. Joseph Mercy Oakland Hospital, Pontiac, MI 48341-5023, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Martí-Fàbregas J, Martínez-Ramírez S, Martí-Vilalta JL. Re: The Stroke Outcomes and Neuroimaging of Intracranial Atherosclerosis (SONIA) trial. Neurology 2008; 70:1296; author reply 1296-7. [PMID: 18391165 DOI: 10.1212/01.wnl.0000312112.79733.ec] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
42
|
Dougherty G, Johnson MJ. Clinical validation of three-dimensional tortuosity metrics based on the minimum curvature of approximating polynomial splines. Med Eng Phys 2008; 30:190-8. [PMID: 17419088 DOI: 10.1016/j.medengphy.2007.02.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2006] [Revised: 02/22/2007] [Accepted: 02/24/2007] [Indexed: 11/18/2022]
Abstract
The clinical recognition of abnormal vascular tortuosity is important in the diagnosis of many diseases. Metrics based on three-dimensional (3D) curvature, using approximating polynomial spline-fitting to "data balls" centered along the mid-line of the vessel, minimize digitization errors and give tortuosity values largely independent of the resolution of the imaging system. We applied two of these metrics to a number of clinical vascular systems, using both 2D and 3D datasets. Using abdominal aortograms of low tortuosity, we established their validity by their strong correlation with the ranking of an expert panel of three vascular surgeons. The values of the Spearman rank correlation coefficient between our rankings, using a data ball radius of one-quarter of the local vessel radius, and the average ranking of the expert panel were 0.96 (with a 95% confidence interval of [0.91, 0.99]) for the mean curvature and 0.98 ([0.94, 0.99]) for the root-mean-square (RMS) curvature. These confidence intervals indicate that our automated analysis is producing rankings whose reliability is similar to that of a human expert, and is significantly better than that achieved with existing algorithms. The metrics provided good discrimination between vessels of different tortuosity for both 2D and 3D datasets, and produced values sufficiently discriminating to assess the relative utility of arteries for endoluminal repair of aneurysms.
Collapse
Affiliation(s)
- Geoff Dougherty
- Applied Physics, California State University Channel Islands, Camarillo, CA 93012, USA.
| | | |
Collapse
|
43
|
Kelle S, Thouet T, Tangcharoen T, Nassenstein K, Chiribiri A, Paetsch I, Schnackenburg B, Barkhausen J, Fleck E, Nagel E. Whole-heart coronary magnetic resonance angiography with MS-325 (Gadofosveset). Med Sci Monit 2007; 13:CR469-CR474. [PMID: 17968293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
BACKGROUND Magnetic resonance coronary angiography (MRCA) is limited by a low signal-to-noise-ratio (SNR), low spatial resolution, and limited coverage of the coronary artery tree. These aspects might be significantly improved by intravascular contrast agents. The aim of the study was to evaluate the feasibility of whole-heart contrast-enhanced MRCA using the intravascular contrast agent gadofosveset, formerly known as MS-325. MATERIAL/METHODS Free-breathing navigator-gated MRCA using a single 3D volume with transversal slice orientation before and after injection of MS-325 (0.05 mmol/kg body-weight) was performed in 17 volunteers (6 men, aged 30+/-8 years). Signal intensities from the myocardium and left ventricular blood were assessed for non-enhanced and contrast-enhanced images. Signal-to-noise ratio of blood and contrast-to-noise ratios (CNR) were calculated. Image quality (0: no visualization, 1: nondiagnostic, 2: moderate, 3: good, 4: excellent) and MR angiograms (15-segment model following AHA/ACC guidelines) were evaluated. Visible vessel length and vessel sharpness were measured and visible coronary artery segments assessed. RESULTS MR coronary artery imaging using MS-325 was successfully performed in 16 volunteers. One volunteer was excluded from the analysis because of trigger problems. SNR did not improve significantly after administration of MS-325 (14.1 vs. 14.6, p=NS), but CNR did (8.03 vs. 12.73, p<0.001). Image quality increased with MS-325 from 2.5+/-0.4 to 2.8+/-0.3 (p<0.05). Overall vessel length and vessel sharpness improved significantly after MS-325 administration (p<0.05). CONCLUSIONS Whole-heart coronary MRA with the intravascular contrast agent MS-325 enables significant improvement in CNR, blood-myocardial contrast, image quality, visible vessel length, and vessel sharpness over non-contrast MRCA.
Collapse
Affiliation(s)
- Sebastian Kelle
- Department of Internal Medicine/Cardiology, Deutsches Herzzentrum Berlin, Germany.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Barnhart HX, Lokhnygina Y, Kosinski AS, Haber M. Comparison of concordance correlation coefficient and coefficient of individual agreement in assessing agreement. J Biopharm Stat 2007; 17:721-38. [PMID: 17613650 DOI: 10.1080/10543400701329497] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
In method comparison and reliability studies, it is often important to assess agreement between multiple measurements made by different methods, devices, laboratories, observers, or instruments. For continuous data, the concordance correlation coefficient (CCC) is a popular index for assessing agreement between multiple methods on the same subject where none of the methods is treated as reference. Barnhart et al. (2007) proposed coefficient of individual agreement (CIA) to assess individual agreement between multiple methods for situations with and without a reference method extending the concept of individual bioe-quivalence from the FDA 2001 guidelines. In this paper, we propose a new CCC for assessing agreement between multiple methods where one of the methods is treated as reference. We compare the properties of the CCC and CIA and their dependency on the relative magnitude of between-subject variability and within-subject variability. The relationship between CCC and CIA as well as the impact of between-subject variability are presented algebraically and graphically. Several examples are presented to explain the interpretation of the CCC and CIA values.
Collapse
Affiliation(s)
- Huiman X Barnhart
- Department of Biostatistics and Bioinformatics, Duke Clinical Research Institute, Duke University, Durham, North Carolina 27715, USA.
| | | | | | | |
Collapse
|
45
|
Abstract
Evaluating agreement between measurement methods or between observers is important in method comparison studies and in reliability studies. Often we are interested in whether a new method can replace an existing invasive or expensive method, or whether multiple methods or multiple observers can be used interchangeably. Ideally, interchangeability is established only if individual measurements from different methods are similar to replicated measurements from the same method. This is the concept of individual equivalence. Interchangeability between methods is similar to bioequivalence between drugs in bioequivalence studies. Following the FDA guidelines on individual bioequivalence, we propose to assess individual agreement among multiple methods via individual equivalence using the moment criteria. In the case where there is a reference method, we extend the individual bioequivalence criteria to individual equivalence criteria and propose to use individual equivalence coefficient (IEC) to compare multiple methods to one or multiple references. In the case where there is no reference method available, we propose a new IEC to assess individual agreement between multiple methods. Furthermore, we propose a coefficient of individual agreement (CIA) that links the IEC with two recent agreement indices. A method of moments is used for estimation, where one can utilize output from ANOVA models. The nonparametric and bootstrap approaches are used for inference. Five examples are used for illustration.
Collapse
Affiliation(s)
- Huiman X Barnhart
- Department of Biostatistics and Bioinformatics, Duke Clinical Research Institute, Duke University, Durham, North Carolina 27715, USA.
| | | | | |
Collapse
|
46
|
Abstract
The concordance correlation coefficient (CCC) is a popular index for measuring the reproducibility of continuous variables. We examine two resampling approaches, permutation testing and the bootstrap, for conducting hypothesis tests on dependent CCCs obtained from the same sample. Resampling methods are flexible, require minimal marginal and joint distributional assumptions, and do not rely on large sample theory. However, the permutation test requires a restrictive assumption (exchangeability) which limits its applicability in this situation. Simulation results indicate that inference based on the bootstrap is valid, although type-I error rates are inflated for small sample sizes ( approximately 30). For illustration we analyze data from a carotid stenosis screening study.
Collapse
Affiliation(s)
- John M Williamson
- Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA.
| | | | | |
Collapse
|
47
|
|
48
|
Feldmann E, Wilterdink JL, Kosinski A, Lynn M, Chimowitz MI, Sarafin J, Smith HH, Nichols F, Rogg J, Cloft HJ, Wechsler L, Saver J, Levine SR, Tegeler C, Adams R, Sloan M. The Stroke Outcomes and Neuroimaging of Intracranial Atherosclerosis (SONIA) Trial. Neurology 2007; 68:2099-106. [PMID: 17409371 DOI: 10.1212/01.wnl.0000261488.05906.c1] [Citation(s) in RCA: 211] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Transcranial Doppler ultrasound (TCD) and magnetic resonance angiography (MRA) can identify intracranial atherosclerosis but have not been rigorously validated against the gold standard, catheter angiography. The WASID trial (Warfarin Aspirin Symptomatic Intracranial Disease) required performance of angiography to verify the presence of intracranial stenosis, allowing for prospective evaluation of TCD and MRA. The aims of Stroke Outcomes and Neuroimaging of Intracranial Atherosclerosis (SONIA) trial were to define abnormalities on TCD/MRA to see how well they identify 50 to 99% intracranial stenosis of large proximal arteries on catheter angiography. STUDY DESIGN SONIA standardized the performance and interpretation of TCD, MRA, and angiography. Study-wide cutpoints defining positive TCD/MRA were used. Hard copy TCD/MRA were centrally read, blind to the results of angiography. RESULTS SONIA enrolled 407 patients at 46 sites in the United States. For prospectively tested noninvasive test cutpoints, positive predictive values (PPVs) and negative predictive values (NPVs) were TCD, PPV 36% (95% CI: 27 to 46); NPV, 86% (95% CI: 81 to 89); MRA, PPV 59% (95% CI: 54 to 65); NPV, 91% (95% CI: 89 to 93). For cutpoints modified to maximize PPV, they were TCD, PPV 50% (95% CI: 36 to 64), NPV 85% (95% CI: 81 to 88); MRA PPV 66% (95% CI: 58 to 73), NPV 87% (95% CI: 85 to 89). For each test, a characteristic performance curve showing how the predictive values vary with a changing test cutpoint was obtained. CONCLUSIONS Both transcranial Doppler ultrasound and magnetic resonance angiography noninvasively identify 50 to 99% intracranial large vessel stenoses with substantial negative predictive value. The Stroke Outcomes and Neuroimaging of Intracranial Atherosclerosis trial methods allow transcranial Doppler ultrasound and magnetic resonance angiography to reliably exclude the presence of intracranial stenosis. Abnormal findings on transcranial Doppler ultrasound or magnetic resonance angiography require a confirmatory test such as angiography to reliably identify stenosis.
Collapse
Affiliation(s)
- E Feldmann
- Department of Clinical Neurosciences, Brown University School of Medicine, Providence, RI 02903, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Abstract
The interobserver variation in the magnetic resonance (MR) location of cerebral vein and dural sinus thrombosis (CVT) has not been previously reported. Four independent observers rated a convenience sample of 40 MR/MR angiographies to assess whether or not each dural sinus and major cerebral veins were occluded. Interobserver reliability was measured using kappa statistics. Interobserver agreement was comparable between the six pairs of raters. Agreement was excellent for thrombosis of the deep cerebral venous system (kappa = 1.00), cerebellar veins (kappa = 1.00), superior sagittal sinus (kappa range: 0.82-1) and right jugular vein (kappa range: 0.84-0.95); good to excellent for the right transverse/sigmoid sinus (kappa range: 0.75-0.90) and the left jugular vein (kappa range: 0.65-0.85); moderate to excellent for the left lateral sinus (kappa range: 0.59-0.78) and the straight sinus (kappa range: 0.59-0.92); poor to good for the cortical veins (kappa range: 0.02-0.65). Agreement between observers varies with the location of CVT. It is good or excellent for most of the occluded sinus and veins, except for the cortical veins. This study suggests that information on the location of CVT can be reliably collected and used in multicentre studies.
Collapse
Affiliation(s)
- J M Ferro
- Serviços de Neurologia, Hospital de Santa Maria, Lisboa, Portugal.
| | | | | | | |
Collapse
|
50
|
Venkatachari AK, Halliburton SS, Setser RM, White RD, Chatzimavroudis GP. Noninvasive quantification of fluid mechanical energy losses in the total cavopulmonary connection with magnetic resonance phase velocity mapping. Magn Reson Imaging 2006; 25:101-9. [PMID: 17222721 DOI: 10.1016/j.mri.2006.09.027] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Accepted: 09/09/2006] [Indexed: 11/29/2022]
Abstract
A major determinant of the success of surgical vascular modifications, such as the total cavopulmonary connection (TCPC), is the energetic efficiency that is assessed by calculating the mechanical energy loss of blood flow through the new connection. Currently, however, to determine the energy loss, invasive pressure measurements are necessary. Therefore, this study evaluated the feasibility of the viscous dissipation (VD) method, which has the potential to provide the energy loss without the need for invasive pressure measurements. Two experimental phantoms, a U-shaped tube and a glass TCPC, were scanned in a magnetic resonance (MR) imaging scanner and the images were used to construct computational models of both geometries. MR phase velocity mapping (PVM) acquisitions of all three spatial components of the fluid velocity were made in both phantoms and the VD was calculated. VD results from MR PVM experiments were compared with VD results from computational fluid dynamics (CFD) simulations on the image-based computational models. The results showed an overall agreement between MR PVM and CFD. There was a similar ascending tendency in the VD values as the image spatial resolution increased. The most accurate computations of the energy loss were achieved for a CFD grid density that was too high for MR to achieve under current MR system capabilities (in-plane pixel size of less than 0.4 mm). Nevertheless, the agreement between the MR PVM and the CFD VD results under the same resolution settings suggests that the VD method implemented with a clinical imaging modality such as MR has good potential to quantify the energy loss in vascular geometries such as the TCPC.
Collapse
Affiliation(s)
- Anand K Venkatachari
- Laboratory of Biofluid Mechanics and Cardiovascular Imaging, Department of Chemical and Biomedical Engineering, Cleveland State University, Cleveland, OH 44115-2425, USA
| | | | | | | | | |
Collapse
|